Protective helmet

ABSTRACT

A shock-absorbing helmet for sporting activities, e.g., including at least one damping layer covering a portion of the user&#39;s skull and an inner cap adapted to be inserted, at least partially, between the protective layer and the skull, the inner cap comprising at least one bladder. The inner volume of the bladder of the helmet defines an initial inner cap thickness, at least locally, in an initial customization configuration, and the helmet includes a mechanism for adjusting the inner volume of the bladder enabling, upon compression of the bladder, the discharge of a portion of the fluid contained in the bladder, the decrease in the inner volume of the bladder providing a localized reduction in the initial inner cap thickness in order to conform the inner cap to the morphology of the user&#39;s skull.

CROSS-REFERENCE TO RELATED APPLICATION

This application is based upon French Patent Application No. 12/02159, filed Aug. 1, 2012, the disclosure of which is hereby incorporated by reference thereto in its entirety, and the priority of which is claimed under 35 U.S.C. §119.

BACKGROUND

1. Field of the Invention

The invention relates to a protective helmet, such as a helmet for sporting activities. In particular, but not exclusively, the invention relates to a helmet intended for the practice of sports, including winter sports, such as skiing and snowboarding, for example, but also cycling, mountaineering, rock climbing, ice hockey, ice skating, football, roller skating.

2. Background Information

In a known fashion, a helmet includes a structural arrangement for protecting the head, which protects the skull from impacts occasioned by the user falling or being involved in a collision, or impacts occasioned by an object directed toward the user. Such protective arrangement is typically comprised of a shell and a shock-absorbing cap. The shell can be rigid, being made, for example, by injection molding a thermoplastic material such as ABS (Acrylonitrile Butadiene Styrene). Alternatively, the shell can be a skin having no inherent rigidity, but acquiring some rigidity once such skin is connected to the shock-absorbing cap. For example, the skin can be made by shaping a sheet of PVC (Polyvinyl Chloride) or PC (Polycarbonate). Typically, the shock-absorbing cap is made of a foamed material such as EPS (Expanded Polystyrene) or EPP (Expanded Polypropylene). To guarantee good comfort for the user, a helmet can be equipped with a comfort structure, which can be in the form of an inner cap made, for example, of foam covered with fabric.

A number of devices are known from the prior art, which make it possible to adapt the inner volume of the helmet to the head of the user.

For example, the patent document U.S. Pat. No. 6,647,556 proposes to adapt the volume by sliding the various portions constituting the helmet with respect to one another. Such a device is difficult to adjust and makes the helmet relatively heavy for the user to wear.

Another example is provided by the patent document FR 2 888 729, by which the inner volume of the helmet is to be modified by inflating a bladder of an inner cap using a manual pump. The bladder is initially deflated. The inner volume of the bladder is substantially zero. The inner cap has a low thickness corresponding to that of the walls of the bladder. The circumference of the inner cap is greater than the circumference of the skull of the user. As a result, the user can easily put on the helmet due to the clearance between the inner cap and the skull. To adjust the inner cap to the wearer's morphology, the wearer inflates the bladder using the manual pump until the inner cap is properly retained. Advantageously, the inner cap incorporates a manually-actuatable air exhaust valve for evacuating air from the bladder when it is no longer necessary to adapt the helmet to the morphology of the user's skull. Such a device is not optimal for use, given the need to adapt the inner volume of the helmet, via manual inflation, almost every time that this helmet is worn. The inflation may take time, depending upon the morphology of the skull. Furthermore, excessive pressure in the bladder can cause discomfort for the user. Indeed, and true for all of the volume adaptation devices, it is absolutely necessary to prevent the helmet from locally exerting pressure causing discomfort on the wearer's head. Adjusting the pressure on the skull is not straightforward with this system, as it is dependent upon a defined insufflation inherent in the pump. This active principle of volume adjustment does not allow for a fast and automatic adjustment of the helmet to the morphology of the user's skull.

SUMMARY

In view of the disadvantages of the prior art, there exists a need to provide a protective helmet, in particular for sporting activities, that includes an arrangement to customize its inner volume to the wearer, which arrangement is fast, easy to use, compact, inexpensive, and which adapts to all types of skull morphology. In a particularly advantageous embodiment, this customization arrangement is automatic.

To this end, the invention provides a helmet for sporting activities including at least one damping layer covering a portion of the head of a user, and an inner cap adapted to be inserted, at least partially, between the aforementioned damping layer and the skull, the inner cap comprising at least one bladder.

The inner volume of the bladder of the helmet defines an initial inner cap thickness, at least locally, in an initial customization configuration, the helmet further includes a mechanism for adjusting the inner volume of the bladder and which, upon compression of the bladder, enables the discharge of a portion of the fluid contained in the bladder, this decrease in the inner volume of the bladder providing a localized reduction in the initial thickness of the inner cap, in order to conform the inner cap to the morphology of the user's skull.

Thus, the bladder of the inner cap of the helmet is inflated prior to customization. Then, to adapt the helmet to the head morphology, it suffices to push the helmet down onto the head to a comfortable position, thereby creating excess pressure that causes the air under overpressure to escape through the adjusting mechanism. The adjusting mechanism then prevents the bladder from reflating, and the interior of the helmet maintains the “imprinted” shape of the head. The inner cap conforms to the morphology of the skull.

The helmet according to the invention can have one or more of the following features, taken individually or in combination:

-   -   the adjusting mechanism includes a device for maintaining an         underpressure in the inner volume of the bladder, relative to         the pressure of the inner volume of the bladder when in an         initial customization configuration;     -   the inner volume of the bladder is at ambient pressure, when the         bladder is in its initial configuration;     -   the adjusting mechanism includes a device for the automatic         discharge of a portion of the fluid contained in the bladder         upon compression of the bladder.     -   the adjusting mechanism includes a non-return valve. According         to one embodiment, the adjusting mechanism includes an element         for inhibiting the non-return valve, which enables a functional         vent for reflating the bladder. According to a variation, only         the inhibiting element enables the bladder to be reflated by         connecting the bladder inner volume to the ambient air;     -   the inner cap includes an arrangement for automatically         reflating the bladder. In a particular embodiment, this         automatic reflation arrangement is a compressible foam.         According to a specific one of plural alternatives, the         compressible foam is confined either by two panels welded to one         another, or by a folded panel whose edges are welded to one         another; or by a sleeve welded at its ends. In a specific         embodiment, the density of the compressible foam is between 20         kg/m³ and 50 kg/m³. In a specific embodiment, the thickness of         the compressible foam is between 5.0 mm and 12 mm;     -   the inner cap includes a substantially circumferential band         within the helmet, corresponding to the total or partial         circumference of the head of a user;     -   the helmet comprises an inflation chamber arranged in the area         of the portion of the helmet adapted to be in contact with the         sub-occipital part of the user's skull, and an element of the         mechanism for adjusting the bladder is connected to the         inflation chamber for inflating the bladder, at least partially,         in case of a reduction in the volume of the fluid contained in         the bladder during the adaptation, at least partial, of the         helmet to the morphology to the user's skull.

The invention further relates to a method for customizing a protective helmet to the morphology of the skull of a user, including the following:

-   initializing the bladder in its initial configuration, in which the     inner circumference of the inner cap is less than the circumference     of the skull in the area of the contact zones; and -   positioning the helmet on the head of the user causing the     automatic, or manually-induced, discharge of a portion of the fluid     contained in the bladder upon compression of the bladder in order to     conform the inner cap to the morphology of the skull.

BRIEF DESCRIPTION OF DRAWINGS

Other characteristics and advantages of the invention will become apparent from the description that follows, with reference to the annexed drawings illustrating, by way of non-limiting embodiments, how the invention can be embodied, and in which:

FIG. 1 is a cross-sectional view of a helmet according to the invention;

FIG. 2 is a cross-sectional view of a helmet according to the invention positioned on the head of a user when adapting the helmet to the morphology of the user's head;

FIG. 3 is a cross-sectional view of a helmet according to the invention when reinitializing the inner cap of the helmet;

FIG. 4 is a cross-sectional view of a second embodiment of a helmet according to the invention;

FIG. 5 is a cross-sectional view of a third embodiment of a helmet according to the invention; and

FIG. 6 a schematic flowchart illustrating the various steps in obtaining the cushion for a helmet according to the invention.

DETAILED DESCRIPTION

FIG. 1 shows a cross section of a protective helmet 1 intended for sporting activities, in particular winter sports, and more particularly gliding sports such as skiing, snowboarding, etc.

The helmet 1 includes a plurality of protective layers. In this example, the helmet includes a shell 2 and at least one damping layer 3, also called a cap, lining the inside of the shell 2. The cap 3 is adapted to cover a portion of the skull 71 of the user.

The shell is 2 made by injection molding a thermoplastic material, such as ABS (Acrylonitrile Butadiene Styrene) or PC (Polycarbonate), for example.

The cap 3 is made, for example, out of a foamed material such as EPS (Expanded Polystyrene) or EPP (Expanded Polypropylene). It can be a single layer or multiple layers assembled, such multiple layers comprising identical or different materials and/or structures.

In addition, the helmet 1 includes an inner cap 4 adapted to be interposed between the cap 3 and the head 7 of a helmet wearer (see FIG. 2). The inner cap 4 comprises a bladder 40 structured and arranged to receive a fluid, namely air in this example.

It is important to distinguish the cap 3 from the inner cap 4. The cap 3 provides shock-absorption. Due to this layer, impacts are damped. The damping layer thus plays a direct head protection role. According to this invention, the inner cap 4 is a comfort element that has a minor effect on the protection of the head. This additional layer improves the fit of the helmet by providing a better retention of the protective layers around the head of the user.

The helmet 1 also includes a mechanism 5 for adjusting the inner volume of the bladder. This adjusting mechanism 5 is connected to the bladder 40. It comprises a non-return valve 51 enabling the discharge of a portion of the air contained in the bladder 40 upon compression of the bladder. This valve allows air inside the bladder 40 to escape outward, for example (see the arrows Ap in FIG. 2), but it prevents outside air from entering into the bladder. This valve enables an at least partial adaptation of the helmet to the morphology of the user's head, as will be explained below.

To customize the helmet to the morphology of the wearer, the wearer performs the method described below.

First, the user initializes the bladder 40 so that a certain, non-zero volume of air fills the bladder. This volume at least locally creates an inner cap thickness Ei. This thickness Ei can be different at the front, top, or rear of the inner cap. In this configuration, the inner envelope of the inner cap 4 is smaller than the outer envelope 71 of the skull. Similarly, the inner circumference of the inner cap is less than the circumference of the skull in the area of the concordance zones.

Second, the user inserts his/her head 7 in the helmet until the inner cap conforms to the morphology of the user's skull. This creates overpressure in the bladder 40. The air in the bladder 40 is then discharged through the non-return valve 51, which is an element of the adjusting mechanism 5. This non-return valve ensures air circulation in only one direction, namely, that of deflating the bladder. The non-return valve prevents the bladder 40 from reflating. It thus makes it possible to reduce the inner volume of the bladder upon compression of the bladder. This reduction in volume causes an at least localized reduction in the inner cap thickness. The inside of the helmet then maintains the shape of the head 7 thus “imprinted”.

These operations have the advantage of being simple and fast to carry out. The adjustment occurs concurrently when the user puts on the helmet. This is a passive principle in the sense that there is no need for additional specific customization action after positioning the helmet on the head, unlike the prior art devices which require manual inflation of the bladder. The customization occurs simultaneously with the positioning of the helmet on the head, which makes it possible to save time. Furthermore, this customization enables the inner cap to conform precisely to the morphology of the user's skull. The second operation, during which the head is inserted within the helmet, makes it possible to create an accurate imprint of the skull on the inner cap, which improves wearing comfort.

The non-return valve 51 can be manually actuated by pressing a button, by unscrewing a plug, or by any other expedient. In one embodiment, the valve 51 is not a non-return valve. In this case, air circulation is blocked by the actuator of the valve. For example, the valve can be a simple valve. Advantageously, the non-return valve is automatically triggered by being energized, for example. This valve thus forms a device ensuring the automatic discharge of air once the internal pressure exceeds a threshold, upon compression of the bladder. This automatic aspect further facilitates the customization as no further particular user action is needed to trigger the conformation of the inner cap. The wearer only needs to put on the helmet after initializing the bladder, according to the first operation described above. In the embodiments described below, the non-return valve 51 is automatic.

Any of several solutions for initializing the bladder are possible.

A first solution is to connect the bladder to a pump. Thus, the user inflates the inner volume of the bladder with the pump to obtain an initial inflation pressure in the bladder. When the user dons the helmet, he/she presses on the bladder, and thereby creates an overpressure of the air contained in the bladder. The air is then discharged through the non-return valve calibrated to a predetermined pressure, greater than or equal to the initial inflation pressure. The inner volume of the bladder decreases, and thereby enables the desired morphological adaptation. The air remaining in the reduced inner volume of the bladder is still under pressure.

A second solution, with reference to FIGS. 1 to 6, is to incorporate a shaping arrangement in the helmet for maintaining a predetermined initial inner volume when the inner volume of the bladder is at ambient pressure. Accordingly, simply connecting the bladder to the ambient air provides a certain inner volume of the bladder resulting in a non-zero initial thickness Ei of the inner cap, at least locally. This configuration corresponds to the initial customization configuration.

As the helmet is being positioned on the head, the skull presses on the bladder, thereby creating an overpressure of the air contained in the bladder. The air is then discharged through the non-return valve connected to the bladder, and the inner volume of the bladder decreases, which enables the desired morphological adaptation, at least partially. Unlike the first solution, the air remaining in the bladder with reduced inner volume is under underpressure. For this, it is necessary for the non-return valve 51, which is an element of the adjusting mechanism 5, to allow maintaining an underpressure in the inner volume upon compression of the bladder. It is this underpressure that provides the localized reduction in the inner cap thickness by reducing the inner volume.

To initialize the bladder, it suffices to connect the bladder to the ambient air. Therefore, the shaping arrangement acts on the inner volume of the bladder so that it reaches the predetermined initial inner volume. For this, the adjusting mechanism 5 also includes an element 52 for inhibiting the non-return valve 51, which enables a functional vent for reflating the bladder. The shaping arrangement described above corresponds to the arrangement for automatic reflation of the bladder as it makes it possible to restore the initial inner volume of the bladder corresponding to the initial customization configuration.

This second solution is advantageous because it can be compact and easily integrated into the helmet, as there is no need for a pump and the inhibiting element can be a simple manually-actuatable non-return valve. In addition, it is easy to use because the user's action is simple, i.e., pressing a button versus inflating the bladder by pressing it successively.

Other solutions are possible. For example, a single-customization inner cap can be provided. In this case, the adjusting mechanism does not allow the initialization of the inner cap. The inner cap has an initial inner volume. The positioning of the helmet flushes the air under overpressure in order to conform the inner cap to the morphology of the user's head. The helmet is then adjusted without possibility of being reinitialized.

Embodiments corresponding to the second solution described above and in

FIGS. 1 to 6 will now be described in detail.

According to the first embodiment, shown in FIGS. 1 to 3, the inner cap 4 includes two panels 41 and 42, the one 41 of which is closer to the cap 3, and the other 42 of which is adapted to be closer to the head 7. These two panels 41 and 42 can be made of a plastic material or fabric incorporating a waterproof film and a heat-sealable film to improve the contact with the user's skull and, therefore, the wearing comfort. These two panels 41 and 42 are sealed in relation to one another to form the impervious bladder 40, confining, therebetween, at least one compressible foam element 61, 62, 63, 64. This compressible foam constitutes the shaping arrangement or, in other words, the arrangement for automatic reflation of the bladder.

Other solutions for the structure of the bladder 40 are within the scope of the invention. It can be a single folded panel whose edges are sealed to one another, or a sleeve sealed at its ends. Alternatively, it can be a panel directly attached to the impervious inner wall of the cap 3.

In the example shown in FIGS. 1 to 3, the inner cap 4 covers the entire upper portion of the skull 71. The bladder 40 contains four distinct foam elements 61, 62, 63, 64. To keep these foam elements in place in the inner cap 4, the inner cap can include chambers 461, 462, 463, 464 communicating with one another through openings, demarcated by weld lines interrupted between the two walls of the bladder, that is to say, the panels 41, 42. Alternatively, the inner cap 4 can include a plurality of distinct bladders 40 connected by conduits. It is therefore important that the elements 51, 52 of the adjusting mechanism 5 be connected to the network of chambers or bladders.

FIG. 4 illustrates another embodiment in which an inner cap 104 covers a substantially circumferential band within the helmet 101 corresponding to a total head circumference of a user. This configuration provides better ventilation of the skull. Furthermore, it has been noticed that the interface zone is sufficient to ensure a comfortable and adequate retention of the helmet. In this case, there is only one bladder 1040 in which a foam element 106 is housed.

The selection of compressible foam is crucial in obtaining an effective customization. Good results are achieved with a foam density ranging between 20 kg/m³ and 50 kg/m³, and/or with a foam thickness ranging between 5.0 mm and 12 mm, at least on top of the skull and/or the front portion the skull. Locally, it can be advantageous to have a greater foam thickness, such as in the rear zone of the skull, for example. These features make it possible to have an adequate adaptation amplitude without the user having the impression of using the wrong size when first trying on the helmet 1. With this configuration, the foam element(s) enhance the user's sensations of wearing comfort and morphological adaptation during customization and use. The foam is made of polyurethane, for example.

A shape memory effect can thus be obtained within the helmet 1. By pressing the helmet 1 on the head 7 (see FIG. 2), the air is flushed out of the cells of the foam elements 61, 62, 63, 64 to the outside, via the non-return valve 51. The bladder 40 thus retains its shape as the non-return valve 51 prevents air from going into the bladder 40. The inner volume of the bladder 40 is under underpressure, which causes the compression of the foam elements 61, 62, 63, 64 by the walls of the bladder 40, i.e., the panels 41, 42. The inner cap 4 remains flattened.

Due to its low-density and elasticity, the foam elements 61, 62, 63, 64 tend to space the two panels 41 and 42 apart, which makes it possible to obtain the self-inflating effect of the bladder 40 when it is no longer under underpressure.

However, given that the bladder, formed by the two panels 41 and 42 is impervious, inflation can occur only if the non-return valve 51 is inhibited, that is to say, it lets the outside air into the bladder. Otherwise, the thickness of the bladder 40 remains stable, depending upon the internal pressure of the bladder. This is why the adjusting mechanism 5 includes the element 52 for inhibiting the non-return valve 51, as mentioned above. In the example illustrated, the non-return valve 51 and the inhibiting element 52 are two distinct members of the adjusting mechanism 5. Alternatively, these two members can be combined to form a single device. In this case, the inhibiting element 52 acts in the area of the non-return valve 51, for example by forcing the opening of the non-return valve.

The inhibiting element 52 enables a functional vent for reflating the bladder. Thus, this inhibition suppresses the underpressure inside the bladder 40. The interior of the bladder returns to ambient pressure. The foam elements 61, 62, 63, 64, arranged within the bladder 40 tends to reassume its initial shape as it is no longer compressed by the walls 41, 42 of the bladder, compression resulting from the underpressure, and therefore pushes back the walls of the bladder. As a result, the foam elements help the bladder in restoring its initial volume. The inner cap and the bladder resume their initial customization configuration, with an associated inner cap thickness Ei.

An arrangement for automatic reflation or shaping of the bladder other than the use of compressible foam is within the scope of the invention. Such arrangement may comprise springs or leaf springs. This automatic reflation arrangement has a spring effect enabling an increase in the inner volume of the bladder in order to restore the initial inner volume of the bladder.

A self-gripping fastener 8, such as a hook-and-loop fastening device, is provided to retain the inner cap 4, 104 against the cap 3. Other fasteners, such as snap fasteners, clips, etc., are possible.

Advantageously, to improve the perception of the user that the helmet is properly put on and to improve the user's feeling of comfort, an extra foam element 65 is superimposed on the lower foam element 61, only on the rear portion of the inner cap, in the occipital zone. This superposition makes it possible to locally increase the thickness of the inner cap. This excess thickness improves the proprioception of the user. Indeed, when the occipital portion of the wearer's skull 71 reaches this foam excess thickness, it naturally becomes wedged in the rear hollow portion of the skull, beneath the occipital bone. At that moment, the helmet automatically adjusts into a comfortable position for the user, who then has the feeling of having passed a notch and of properly donning the helmet. In a particular embodiment, this additional foam 65 is cut ergonomically to reproduce a contour that is close to the morphology of the skull in the occipital zone. This enables more uniform pressure for retaining the inner cap, and therefore the helmet, on the head, in this rear zone of the skull.

In summary, the customization according to the invention as applied to the embodiment of FIGS. 1 to 3 is as follows:

First, the bladder is initialized, as depicted in FIG. 3. The actuation of the inhibiting element 52 causes the ambient air to enter into the bladder 40 (see the arrows Ai in FIG. 3). The foams elements 61, 62, 63, 64, by reassuming their original shape, therefore exert pressure on the walls 41, 42 of the bladder 40 (see the arrows Pi in FIG. 3). The bladder 40, in other words the inner cap 4, returns to its original customization configuration, as shown in FIG. 1.

Second, as depicted in FIG. 2, the inner cap 4 is adapted to the morphology of the skull 71 of the user. The helmet 1 is pushed down onto the head 7 to a comfortable position. The bladder 40 is compressed, thereby causing the compression of the foam elements 61, 62, 63, 64. The inner volume of the bladder 40 is then under overpressure. The compressed air is then discharged through the non-return valve 51 (see the arrows Ap in FIG. 2). Accordingly, the inner volume of the bladder decreases and is under underpressure, that is to say, at a pressure less than the ambient pressure. This underpressure makes it possible to maintain the compression of the foam elements 61, 62, 63, 64. The inner cap 4 then assumes the shape of the skull 71 in its contact zones. Locally, the inner cap thickness Ec is then less than the initial inner cap thickness Ei, in its initial customization configuration. Therefore, a final customization configuration, for which the inner cap conforms to the morphology of the skull, distinguishes over an initial customization configuration, for which the bladder has returned, or is close to returning, to an initial volume.

FIG. 4 shows another embodiment of the inner cap 104, in the form of a single bladder 1040 forming a peripheral band housing a foam element 106. The functioning principle for the customization remains the same. A non-return valve 1051 and an inhibiting element 1052 of an adjusting mechanism 105 are directly connected to the bladder 1040 of the inner cap 104. An additional foam element 1065 is attached to the foam 106 in the occipital zone.

The customization according to the invention can be repeated as desired, for example to take into account the length of hair at various times, a loan between users, or in the case of a rental of the helmet. It then suffices to actuate the automatic reflation of the bladder as described above.

FIG. 5 shows an alternative embodiment of a helmet according to the invention.

This helmet 201 differs from that of FIG. 4 in that it comprises an inflation chamber 208 in the area of the sub-occipital portion of the skull 71 of the user.

As described above, the helmet 201 includes an inner cap 204 incorporating a bladder 2040 which houses foam elements 206, 2065. This helmet 201 includes a mechanism 205 for adjusting the inner volume of the bladder comprising a non-return valve 2051 and an element 2052 for inhibiting the anti-return valve.

In this embodiment, however, the non-return valve 2051 is provided to be connected to the inflation chamber 208 by a conduit 209. This non-return valve 2051 makes it possible to inflate the inflation chamber 208, at least partially, should the bladder 2040 become deflated during the at least partial adaptation of the helmet to the morphology of the user's head 7.

Therefore, when the air is flushed out of the bladder 2040 by pressing on the helmet 201 positioned on the head 7, the inflation chamber 208 automatically inflates, at least partially, for the sub-occipital portion of the skull 71. This inflation chamber 208 substantially improves usage comfort by protecting a portion of the nape. The head is then better supported.

Thus the bladder 2040 whose inner volume decreases to accommodate the skull morphology, on the one hand, and the inflation chamber 208 whose inner volume increases to come into contact with the sub-occipital portion of the skull, on the other hand, ensure that the helmet properly fits. A negative imprint is obtained on one side, in the sense that the shape of the skull fits into the bladder 2040, while a positive imprint is obtained on the other side, in the sense that the retaining device 208 becomes deformed to fill the empty space between the inner cap and the head.

In a particular embodiment, the air volume in the bladder 2040, when fully inflated, is provided to be greater than the volume of the inflation chamber 208, when inflated, such as between 1.5 and 2.0 times the volume of the inflation chamber 208, when inflated. This takes into account that the air is not completely flushed out of the bladder 2040 during the adaptation.

To prevent the inflation chamber 208 from bursting, it is equipped with a pressure relief valve 210 which makes it possible to discharge the excess air from the inflation chamber. The pressure relief valve can be an automatic non-return valve, a manual valve, or another type of valve.

If the inflation chamber 208 is not sufficiently inflated, additional inflation can be provided using an inflating device, not shown, connected to the inflation chamber 208. Such a construction is described, for example, in the patent document FR 2 888 729.

Other alternatives for this embodiment are within the scope of the invention.

For example, the bladder 2040 can also be connected to the ambient air through a second valve, in addition to the non-return valve in 2051 connected to the inflation chamber 208. This second valve makes it possible to avoid overinflating the bladder 2040 if the non-return valve 2051 is blocked.

Alternatively, the inflation chamber 208 incorporates a foam for shaping the inflation chamber to get close to the skull faster. The operation for inflating the chamber can be similar to that for the bladder 2040. The foam would serve as a shaping device that tends to act on the walls of the inflation chamber once the chamber returns to an ambient pressure. In this case, the inflation chamber is first placed under underpressure, for example, by manual pressure on the walls thereof.

Another alternative is to use the inflation chamber 208 as a pump to adjust the inner volume of the bladder 2040. Thus, a non-return valve connecting the inflation chamber to the bladder is added. This valve makes it possible to discharge the excess air from the inflation chamber, upon compression of the latter, toward the bladder. As a result, the initialization of the helmet can be achieved by compressing the inflation chamber. The air discharged from the reflation chamber toward the bladder at least partially suppresses the underpressure in the bladder, which tends to reassume its original shape due to the foam elements 206, 2065. Therefore, the pocket returns to its initial customization configuration. Similarly, the inflation chamber tends to decrease in volume, which facilitates the positioning of the helmet during the next customization.

The above embodiments describe bladders that are inflated with air. Other fluids can also be used to obtain a similar result. For example, the air can be replaced with a gel.

Other combinations of solutions described above are possible.

The inner cap 4 can be produced according to the manufacturing method shown schematically in FIG. 6.

According to operation 50, polyurethane foam layers 61, 62 63, 64, 65, 106, 1065, 206, 2065 and two panels 41 and 42 are cut, the panels being coated, at least at the edges, with a heat-sealable adhesive.

A polyurethane film is used for the panels 41 and 42, the panel 41 of which is coated with velvet to allow self-gripping/detachable fastening within the helmet, and the panel 42 of which is coated with a fleece for good user comfort.

Next, according to operation 52, a stack of two panels 41 and 42 sandwiching the foam layers 61, 62, 63, 64, 65, 106, 1065, 206, 2065 is positioned in a shaping mold having a depth greater than the thickness of the foam layers 61, 62, 63, 64, 65, 106, 1065, 206, 2065.

Further, according to operation 54, heat-sealing is carried out, an operation whereby materials are sealed under heat. Heat-sealing is a high frequency sealing, for example. The two panels 41 and 42 are pressed against one another, in the area of the peripheral edges. An external or internal heat source is applied to the material. This results in an impervious envelope forming the bladder 40.

Due to the fact that the mold has a greater depth than the thickness of the foam elements 61, 62, 63, 64, 65, 106, 1065, 206, 2065, the latter keeps its initial (uncompressed) shape.

Then, in operation 56, a first opening is provided in the bladder 40 thus formed, and an element 51, 1051, 2051 of an adjusting mechanism 5, 105, 205 of the inner volume of the bladder is fixed in this opening. Depending upon the positioning of the bladder 40 in the helmet and to provide better access to the user, the element of the adjusting mechanism 5, 105, 205 is a simple non-return valve 51, 1051, 2051, or it can be an assembly formed by a conduit, for example a plastic tube in which a non-return valve 51, 1051, 2051 is positioned.

In particular, when the adjusting mechanism 5, 105, 205 has a control 52, 1052, 2052 for inhibiting the non-return valve, combined with the latter, a tube can be connected to the bladder with its non-return valve 51, 1051, 2051 to facilitate access to the control.

Then, in operation 58, according to another alternative embodiment, a second opening can be provided in the bladder 40, and a controllable vent 52, 1052, 2052 is sealed or glued for the reflation of the bladder 40. Thus, self-inflation and shape retention are separated. This can be particularly advantageous when the bladder 2040 is coupled to an inflation chamber 208 as shown in FIG. 5.

Alternatively, the operations 56 and 58 may be carried out prior to the operation of panel assembly. Indeed, the elements 51, 1051, 2051, 52, 1052, 2052 of the adjusting mechanism 5, 105, 205 can be fixed on a panel 41, 42 early in the process.

The process is described for a bladder 40 formed from two separate panels 41, 42. This method is applicable mutatis mutandis to other bladder constructions, such as the use of a folded panel whose edges are sealed to one another, or the use of a sleeve sealed at its ends.

It is therefore to be understood that the bladder 40 is a device for customization and comfort which stands out for its ease of use and automatic nature. Thus, a user can completely adapt a helmet to his/her morphology.

At least because the invention is disclosed herein in a manner that enables one to make and use it, by virtue of the disclosure of particular exemplary embodiments of the invention, the invention can be practiced in the absence of any additional element or additional structure that is not specifically disclosed herein. 

1. A protective helmet comprising: at least one damping layer structured and arranged to cover a portion of a skull of a user; an inner cap structured and arranged to be inserted, at least partially, between the damping layer and the user's skull, the inner cap comprising at least one bladder; the bladder having an the inner volume defining an initial inner cap thickness, at least locally, in an initial customization configuration; the protective helmet further comprising an inner volume adjusting mechanism structured and arranged to adjust the inner volume of the bladder; the adjusting mechanism enabling a discharge of a portion of fluid contained in the bladder upon compression of the bladder to decrease the inner volume of the bladder, said decrease in the inner volume of the bladder providing a localized reduction in the initial inner cap thickness in order to conform the inner cap to a morphology of the user's skull.
 2. A protective helmet according to claim 1, wherein: the adjusting mechanism comprises a device for maintaining an underpressure in the inner volume of the bladder in relation to a pressure of the inner volume of the bladder in an initial customization configuration.
 3. A protective helmet according to claim 1, wherein: the inner volume of the bladder in an initial customization configuration is at ambient pressure.
 4. A protective helmet according to claim 1, wherein: the adjusting mechanism comprises a device for automatic discharge of a portion of fluid contained in the bladder upon compression of the bladder.
 5. A protective helmet according to claim 1, wherein: the adjusting mechanism comprising a non-return valve structured and arranged for only deflating the bladder.
 6. A protective helmet according to claim 5, wherein: the adjusting mechanism comprises a device for inhibiting the non-return valve enabling a functional vent for the reflation of the bladder.
 7. A protective helmet according to claim 6, wherein: the inhibiting element only allows reflation of the bladder by connecting the inner volume of the bladder to ambient air.
 8. A protective helmet according to claim 1, wherein: the inner cap comprises an arrangement for automatic reflation of the bladder (40, 1040, 2040) when the inner volume of the bladder is connected to ambient air.
 9. A protective helmet according to claim 8, wherein: the automatic reflation arrangement is a compressible foam.
 10. A protective helmet according to claim 9, wherein: the density of the compressible foam ranges between 20 kg/m³ and 50 kg/m³.
 11. A protective helmet according to claim 9, wherein: the compressible foam has a thickness ranging between 5.0 mm and 12 mm.
 12. A protective helmet according to claim 1, wherein: the inner cap covers a substantially circumferential band within the helmet corresponding to a total or partial circumference of the user's head.
 13. A protective helmet according to claim 1, wherein: the inner cap comprises an excess thickness in the occipital zone.
 14. A protective helmet according to claim 1, further comprising: an inflation chamber arranged in an area of a portion of the helmet structured and arranged to be in contact with a sub-occipital portion of the user's skull; an element of the adjusting mechanism of the bladder is connected to the inflation chamber to inflate inflation chamber, at least partially, in an event of a decrease in a fluid volume contained in the bladder during an at least partial adaptation of the helmet to the morphology of the user's skull.
 15. A method of customizing a protective helmet as defined in claim 1, to the morphology of the skull, the method comprising: initializing the bladder in the initial configuration, in which the inner circumference of the inner cap is less than a circumference of the skull in the area of contact zones; and positioning the helmet on the head of the user, the positioning causing a automatic or manual discharge of a portion of the fluid contained in the bladder, upon compression of the bladder, to conform the inner cap to the morphology of the user's skull. 